const sum = numbs => numbs.reduce((prev, next) => prev + next)

const proxy = new Proxy(sum, {
  apply(target, ctx, args) {
    console.log(`target:`, target) // 自行看控制台输出
    console.log(`ctx:`, ctx)
    console.log(`args:`, args)
    return target(args) * 10
  }
})

console.log(proxy(1, 2, 3)) ///=> 60
console.log('===')
console.log(proxy.call(null, 5, 2)) //=> 70
console.log('===')
console.log(proxy.apply(null, [3, 6])) //=> 90
